To a developing device included in an image forming apparatus utilizing electrophotography, such as a copier, a facsimile machine, and a printer, a toner is supplied using a toner container which is detachably provided to the image forming apparatus. Conventionally, for realization of a preferred supply of toner from the toner container to the developing device, various kinds of toner containers have been suggested.
For example, in patent document 1 (Japanese Laid-Open Patent Application No. 20705/1995 (Tokukaihei 7-20705; published on Jan. 24, 1995)), as shown in FIG. 19, a cylindrical toner container 150 is provided with a spiral guide flute 152 for supplying a toner from an opening 151 to the developing device in a preferred manner, the opening 151 being provided at one end surface of the toner supply container 150, the guide flute 152 being provided around the surface of the toner supply container 150. The guide flute 152 is provided in a spiral manner toward the opening 151 at one end surface of the toner supply container 150. Therefore, by rotation of the toner supply container 150 described in the patent document 1 on its cylinder axis as a rotation axis, toner is transported to the opening 151 along the guide flute 152 in the toner supply container 150, and then the toner is supplied to the developing device.
Patent document 2 (Japanese Laid-Open Patent Application No. 339115/1996 (Tokukaihei 8-339115; published on Dec. 24, 1996)) discloses a developer supply container arranged such that an outlet for releasing developer, provided in a center portion of a developer container body, is hermetically sealed with a seal or the like until the developer container is loaded inside the image forming apparatus. Patent document 3 (Japanese Laid-Open Patent Application No. 348127/1994 (Tokukaihei 6-348127; published on Dec. 22, 1994)) discloses a toner cartridge arranged such that an opening of a cylindrical container is sealed with a seal member, such as seal film, during storage or transportation, which making up a sealed container.
However, in the conventional arts, in detaching/attaching a toner supply device from/to the image forming apparatus, toner spills out from a toner supply port. This causes the problem that the user and the image forming apparatus become dirty with the spilled toner. In order to solve such a problem, arrangements including the following arrangements are widely used: an arrangement in which an openable and closable shutter is provided with respect to the toner supply port for supplying toner from the toner supply device to a toner hopper and an arrangement in which a toner outlet provided to a toner container is adhesively sealed with a film seal member. In a similar manner, the inventors of the present application also contemplated adding a shutter and a seal member and others to the toner supply device. However, it turned out that the use of a conventional, widespread arrangement alone is not an adequate measure to solve the above problem.
More specifically, for example, even if instructions give precautions, for the user who deals with a toner supply device for exchange, not to twist the toner container, the user moves the toner container since the toner container is movable. As a result of this, the seal member having adhesively sealed the toner outlet is unstuck, whereby toner may spill out from the outlet of the toner container in the toner supply device. If, in such a state, the user ignores the precautions and opens a shutter for opening and closing the toner supply port which is provided to the toner supply device, or if the shutter automatically opens during installation of the toner supply device to a printer, toner spills out from the toner supply port of the toner supply device. This causes the problem that the users and the toner supply device become dirty with the spilled toner.